Improvement in the production of oil from cannel-coal



UMTE Sra'res IMPROVEMENT IN THE PRODUCTION OF OIL FROM CANNEL-COAL;

AfrsNr Farce;

Specification forming part of Letters Patent lie-15,505, dated August 12, 1856.

To all whom it may concern.-

Be it known that we, LUTHER ATWOOD and WILLIAM A'rwoon, both of Waltham, in the county of Middlesex and ommonwealth of Massachusetts, chemist-s, have invented or discovered an improved method of obtaining oil from the coals which yield parattine; and we do hereby declarevthat the iollowing is atrue andexact description of the same The nature of our invention and improvement consists in modifying, by chemical processes conjoined with distilling operations, the proximate elements found in the distillates of coals and other bodies which yield parafliine, so as to produce an oleaginous body adapted in a high degree tolubricating purposes. Such coals are known as cannel, Breckenridge, bog-head, brown coal, and Albert coals, peat, and some bitumens.

To render more clear our description we submit that we are the original discoverers, so far as we know, of certain reactions taking place among the constituents of such coals and bitumens which produce ordinarily paratiine-oil and light/oils, and it therefore becomes necessary for us to distinguish coals by new characteristics. \Vc find that coals, when slowly heated to a certain high temperature, varying with the nature of the coal, decompose by changes taking place rapidlynot a species of distillation, but arapid decomposition. This new arrangement of the constituents is always the first effect of heat applied to coals. Excepting a little water, they atiord no fluids until such fluids form from the material of the coal. The condensable'tluid products contain a variety of bodies; but all known coals and bitumens thus treateddivid'e into two classesviz., first, those yielding fluids containing no parailine; second, those producing fluids containingparailine. Thetirstclassincludessome cannels, orcoals having the physical characters of canncls, and some bitumens, all of which yield 'i'h their decomposition semi fluids like. *cominon coal-tar.

For the treatment of such distillates in a way to ati'ord a lubricating-oil, called coup-oil, of certain well-known specific characters we have Letters Patent. The

second class of coals includes most canncls and some bitumcns, brown coals, pea-t, and schists andthe fluids resulting from their decomposition contain para-dine, which is a distinctive feature, and (enables us to class sucli native coals and bitumens under one head in relation to our new manufacture.

Heretoformmuch discrepancy of statement has existed; and in the books wood-tar, peattar, and brown-coal tar have been considered as specially containing parafiine, while eoa'l tar and pinetar weresupposed to contain,

at most, traces of it. It was, however, found that schists, petroleums, and cannelslikc bog-head and Breckenridge-produced it at the lowest temperatures of decomposition, and bog-head coal has become the basis of a manufacture ot'an oil known as parafiine-oil. Those natural bodies which produce parafiiue may be considered as the remainsot waxproducing vegetation. in all that'ha-s been done heretofore to obtain lubricatingoils the greatest care has been observed to so conduct the decomposition of the cannel or brown 'coal that the temperature may below, thereby preventing the decomposition of the 'parafline, which, as a solid, resembles spermaceti, and

when dissolved in eupion formed with itconsti-- rapid decomposition of these cannels and bitumens and their distillates, which produccparatiinc at low temperatures by higher heats suddenly applied, and it is an essential feature of our application that we reject or decompose the paratrine and eupion, so as to avoid the presence of solid parafiine and fluid eupion and form a new olcaginous body, having a high boiling-point, an uncommon oily character, increased density, and resistance to refrigeration. We can use cannel and brown-coal tars from gas-manntacturers,consuming only the coals producing parafline which has then been decomposed, or the waste products ofthemanufacture of light oils containing paraffine from schists, cannels, bitumens, 85c.

The basis of our invention is the {:tisco 'ery that when we distill the hydrocarbons by eat of considerable intensity" rapidly applied repeatedlyat each successive distillation carbon appears as a final product, while the elements I ofthefiuid distillates arrange themselves anew to form a compound which becomes more and more oily in character. By withdrawing interferi-ng bodies we control the resnlic so as to give certainty to the manufacture.

In carrying out our invention we have found an advantage to arise from removing, is; powerful chemical ngents,aoid, alkaline, nndbnsic bodies from the crude products in the course of the operations, so as to prevent-these crude products from reacting to produce other objectionable bodies. Thus when we operate on a .tar-likebody, natural or artificial, we remove, by a large volume ofstrong snlphuric hold, all the naphthalinc and alkaloids, because experience. has shown that these bodies form paranaphthaline at high heats. if after distillation, following in course, more ncphthiiline appearswe remove it in the some way. Some crude materials produce acid hydrocarhonsin breaking up their constituents, and we reverse the course and apply nllzz-ilies to remove them, in every case having inview the nltirnateproduction of e neutral oil of specific characters which are distinctive, from n'llatei'er source it is obtained. crude emitters of different origins, elthongh belonging to the some series, as commonly considered, will notproducc our oil, nor will any member oi distillntione produce it.

The oile which have heretofore been obtained by distillation-from cancel-coals are ihin oils, holding in suspension and solution pernfiine, to which they owe their density,'and sources are the. bog-heed and Erect. ihdge and'like bodies, from which they are obtained by moderated heat in distillntion. It in an essential point in their production that the temperature should not approach 698 Fahrenheit, where paratfine is wholly decomposed, and where the enpion, which boils below 212 Fahrenheit, would be lost. They generally boil at from 450 to 550 Fahrenheit, and are saturated solutions of 'pamifineot 66 Fahrenheit becoming a soft solid at 45 'Feiirenhcit. Yonngs eihwhieb includes the best of that, chise, gircc oft voletile products. at 4410? Fahrenheit which contain ginrnfiine. i enecitic grin/ii varies from 6.836 to 9.858, 1 c it eonnctbe rendered more dense Without decomposing it. Beiega solution of parnifine in the lighter hydrocarbons, it presents two distinct bodies, and owes its lubricating power to the paroili'ne, and as it thickens at anioderntely-low tern pcrctnrc with separation of solid parziiiine, it has not the useful characters we deem eeseniial in our oil.

The oil which We regard as our inrcntlcn eontainc rarely traces of a solid body, which at 32 Fahrenheit appears in necdly crystals, its specific gravity at 60 Fahrenheit. is 0.864 to 0,870, and its olenginous characters are reinor" e,'ezceedi ng in this re t any known oil, we heated it given i" no 'vnpcrot 509 nhci't, and has n nee ingcit t T00 nhrenhcit, relations m lane can with n The eeme'precessee applied to not exist ready formed in any natural bitumen or naphtha, but, is a result of chemical decomposition of hydrocarbons which afford poraliine under the combined action of chemical agents applied in succession with a high heat in distillation.

' in the following description of our processes the art that we do not seek to simply nermrate and pnrifyibodies which have been known be fore and as articles of commerce, but by different stens,appllcablc to the particular-crude matter of the enamels and bitumen-s which produce parzifiine, we arrange chew the coinp0- nent parts of crude distill-nice We do not commence with the coal, but take the timid matter condensed by distilling coals ot' the parafiine mics, however obtained, and subject it, in an ironvcssel, to a. careful washing in water to remove, soluble matter. The

mice must have all its hold hydrocarbons rcmored by mean; of successive portions of cans tic soda or caustic potash at 36Baum, added, agitated, and nithdrnwn tintilth'c solution of alkali nppeariito become no longer changed, even at 2 l2 Fahrenheit; In this step we not only remove the acids present in a free state, but we decompose acid salts or combinations of positive 'nnd negativehydrocarbons, so as to eliminate the bases, while we remove the acid or positive constituent, which is essential to the snccessoli'the other step of the proc esses. The tarryrnatter removed from the last portion of alkali must be distilled from an iron retort by naked beat or'heot aided by stehm, the distillate being rejected until the mesh in 1 the retort shows the temperature of (300 Febrenheit, when the distillate sought for begins to apnea r. B y increasing the heat a large hnl ii of the distillate is obtained, and when the beer pcrnture M750 to 800 Fahrenheit is reached the distillate becomes browneolored, when the process is stopped. in the systematic mnunt'nctureitisnslml to save thcoil boilingsitsifitl i ellrenbeil or below 600 Fahrenheit and mix it with that distilling above 850 Fahrenhcih It thc for their removal usually two hundred fljfilillldfl of oil of vitriol for one hundred gallons i the dietillale, agitation for two hours, and repose in nir at 89 or Qll until subsidence of the acid compounds has taken place. The clear oil most; new be washed. with live gallons of caustic i for one hone *cnndc oi in it will be observedhy those who are skilled in Watched tar-like fluid introducedintoan agi-i mixture has not at this stage a, density of about iyihe reactions in the retort, colored and basic bodies are formed, requiring This sehr ter must be added and the whole agitated one or two hours, the temperature being as high as 100 Fahrenheit to allow of subsidence of all impurities. The clear oil must then be transferred toan iron retort and distilled by the gradual application of heat, with the aid of heated steam above the oil, reserving for future steps the distillate rising between 600 and 800 Fahrenheit only. This operation has produced a new quantity of colored and basic matter, which must be removed by treating one-hundred gallons of the distillate in an agitating apparatus with one hundredpounds of oil of vitriol and violently mixing lortwo hours. After the action of the acid the oil must be washed with five gallons of soda solution at 36 Baum by agitation for one hour and allowing to subside. The resulting product being again distilled with the precautions above stated will have become permanent and uniform. A small amonntof acid'present must be removed by agitating the distillate with three gallons of caustic-soda solution, leaving the oil for the separation of the soda solution at a temperature of 80 or 90 Fahrenheit. After the removal of the oil from the impurities it must be thoroughly washed by jets of steam in the usual manner and subsequently exposed in shallow pans to the suns rays until all moisture has become dissipated.

It is not always necessary to subject the oil to the last distillation here named, as some of the crude distillates are more easily broken up than others; but it is essential that the oil be freed from all bodies having low boiling-points and that the solid hydrocarbons which appear in the first steps be removed by pressing or decomposed almost wholly into an oleaginous body having a density above 0.864.

We are aware that oils for lubrication have before been obtained from coals, bitumens, and sehists which alford paraffine in distillation, and they have been purified by acids and alkalies. These oils are solutions of parafiine in light oils or eupion obtained in the first distillations, deriving their density and essential qualities from the parafline. They do not resemble the heavier uniform oils which result from the decompositions and recompositions taking place in the same distillates at high temperatures, aided by chemical agents applied in large quantities at different steps in the manu fncture, and we disclaim such oils.

We also disclaim mixed crude prod nets hereiofore obtained by distillation from schists, 8.70., and confine ourselves to a. transparent nearly colorless oil, having its boiling-point above 600 Fahrenheit, remaining fluid at 32 Fahrenheit, and of a density above 0.861 at 60 Fahrenheit, which is formed from coals, bitumens, and other bodies affording parat'fine in their treatment by the above processes.

What we claim, and wish to secure by Letters Patent, is-- v An improved oil obtained, by the processes substantially as set forth above, from natural bodies which alone or when mixed aii'ord parafine in destructive distillation, and which oil possesses-the properties above described.

LUTHER ATWOOD. WM. ATWOOD. Witnesses:

JAMES W. RoLLINs, W. H. L. SMITH. 

